Such conveyor type scales are known as three-link scales and are already known. In general, they serve to determine the quantity, with respect to time (volume per time unit) of the material conveyed by the belt. Such scales can be used to determine the quantity conveyed within a given time period, through integration by means of time, or to stop the supply after the required total quantity is obtained, or to continually direct the quantities per time unit to their required set point. The quantity per time is the product of the belt speed and the load per unit of belt length.
Previously known conveyor type scales have links with swivel joints, i.e., hinged joints. Such conveyor type scales are quite well suited for measuring relatively large loads. However, when small loads are also to be measured and small load changes are to be determined, the link friction has a very disruptive effect. When the table is first loaded and afterwards, is unloaded again, it does not return to its exact starting position again. Therefore, link friction causes hysteresis.
In addition, when the measuring sensitivity is high, heating up by means of the conveyor belt sliding over the table, also has a disruptive effect. First of all, the table expands due to heating. In addition to this, often the table is made of a material with relatively low heat conduction, for instance, stainless steel. Therefore, between the upper and lower sides of the table, a difference in temperature results. Accordingly, the tables expand to a greater extent on top, than underneath, so that torques occur in the tables, which cause deformation. Therefore, heating resulting from the conveyor belt friction, causes distortions and agitations of the carrier, i.e., in the tables and links. Depending on the set-up of the transmitting device, these distortions and agitations are transmitted more or less severely to the load-measuring device and can therefore cause errors in measurement.
Conveyor type scales are used in continous operations, i.e., from 8 to 24 hours per day, often under strong vibrations (from 1 to 9 m/s.sup.2). These vibrations reduce the lifespan of the transmitting device and in particular of its links, as well as of the measuring device.